It isn't a big deal. My frame rotted out, what do you want me to do, throw the car away or put a new frame under it?
Can a TJ VIN be used on TJ Unlimited build?
- Thread starter myjeep3
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It isn't a big deal. My frame rotted out, what do you want me to do, throw the car away or put a new frame under it?
Just register it as a custom vehicle, with a new VIN assigned by MA. This will ensure you do not have any hoops to try to cheat/jump through.
Here's the MA laws...
https://malegislature.gov/Laws/GeneralLaws/PartI/TitleXIV/Chapter90/Section2H
https://www.mass.gov/how-to/apply-f...-assigned VIN,7394 to schedule an appointment.+
Following that, it would not be a '98 anymore, rather a '24 (or whenever you finish it) Also note: in the second link, you MUST have proof of purchase (bill of sale, receipts, etc) of all major components so you can prove that they arent stolen.
Here's the MA laws...
https://malegislature.gov/Laws/GeneralLaws/PartI/TitleXIV/Chapter90/Section2H
https://www.mass.gov/how-to/apply-f...-assigned VIN,7394 to schedule an appointment.+
Following that, it would not be a '98 anymore, rather a '24 (or whenever you finish it) Also note: in the second link, you MUST have proof of purchase (bill of sale, receipts, etc) of all major components so you can prove that they arent stolen.
I'm out of town for work right now which means you actually saved me about 4 and a half hours, so thanks.
It's obviously been a while since I even looked at it (basically the day I bought it when I made sure it matches the title). Whatever the last vehicle was that I actually looked at the VIN in that location had a little slot cut out of the dash revealing the VIN plate.
I think that's where the trouble lies. My understanding is that a donor engine has to come from something newer or at least the same as the recipient vehicle. If the LJ is 05-06, you have motive to falsify the VIN and if an inspector looks under the skirt and sees a newer VIN on the tub and frame it will look like you used the older VIN to get away with a swap that meets a less stringent emissions standard.
Yet another reason for you to pursue a custom vehicle VIN/registration. It will protect you, and a buyer if you sell it later...
The fact that the only difference between them is a little number stamped somewhere on a vehicle that could make an engine (that's already on the road) a no no should be absurd to people.
Thank the EPA. Saving the world from hot rodders and lead paint chips
I'm generally not against reasonable emissions laws but this one does seem like it puts a large burden on a hobby enjoyed by a relatively small population, in exchange for preventing an amount of pollution that's insignificant in the big picture.
I agree with the intent that we don't really want people swapping carbureted 1960's SBC's into modern daily drivers by the millions, but no, putting an '04 LS into an '06 should not be illegal. Hell, it probably produces less emissions anyway just from being a more modern engine design.
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What are those connectors going to the transmission, and Tcase for? Though they come from the pcm. No??
The one in the transmission is for your reverse lights. the transfer case has a speed sensor and a switch for the 4x4 indicator light. So, some of it goes back to the PCM but none of it HAS to and the PCM isn't doing any control of any of jt. It reads the speed sensor for engine control features (which you're not using since your LS PCM will be taking care of all that) and speedometer/odometer, and reads the 4x4 switch to light a bulb on the dash. Some people do keep the jeep PCM just to run the factory instrument cluster but I've never thought of that as the cleanest option.
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If all it's doing is feeding data to the instrument cluster, I wouldn't even bother with it. Maybe if I planned to utilize SKIS, but I don't think you can even get the SKIM for the older TJ's anymore.
It won't be connected to the OBD2 port so I don't think there's any reason to update it.
Though the vin is Scanned when they do the annual inspection. Not actually sure.
At this point I don't even know if doing the swap is worth the effort. Here is the frame and tub I found. Owner wants $2500 no title. He already sold the dash but kept the vin tag. Want $3k with title. Looks like tub will be some work
I would want my OBD2 port connected to the engine PCM, and that's what they'll plug into for the scan. I would think they'd want to scan the PCM that actually runs the engine as well. If they scan the Jeep PCM it's gonna be lit up like a Christmas tree with DTCs trying to run an engine that isn't there.
As for how they handle it when they plug into an OBD2 port on a tj and it comes back as a Chevy pickup or whatever, I don't know, but people do it all the time. But thats where what I mentioned earlier comes into play...if you have an 04 LS with matching PCM and an 05-06 VIN on the Jeep, I think that's gonna cause you problems. An 04 LS into a 98 should be fine, but if they dig at all and find the body and frame are an 05, that may be even more trouble. You're probably gonna have to make friends with somebody that does this stuff in your state to figure out what you can actually do.
I know it's more money, but are the LS similar enough between 04 and 06 that you could use an 06 LS PCM?
ok, in that case, put the LJ VIN on the dash, that'll keep the emissions people happy. I don't know if you'd mentioned the years but if so I missed it so I've been assuming based on statistical likelihood/production numbers since most LJ's are 05-06.
Again, note that you ONLY need a Jeep PCM if you absolutely insist on keeping the factory cluster. If you do choose to keep the factory cluster, you just need the PCM that matches the cluster. Use the TJ PCM with the TJ cluster or the LJ PCM with the LJ cluster. IMO, keeping both LJ will probably save you a fair bit of work because I have to assume the harnesses would differ significantly.
The LS PCM will be what the scanner sees and connects to, so the VIN doesn't matter, but if for some reason you end up swapping the PCM, cluster, and the connecting harness from the TJ, the TJ PCM should be able to be programmed for a new VIN. But again...no one is ever gonna hook up to it so it matters none whatsoever.
The LJ has no PCM, cluster, harness, or anything else, it's just a tab and frame. The 98 TJ is complete, so everything would move from TJ to the LJ
Also the LJ being over 15 years old, emission is not required in MA, just safety inspection.
I don't have to use the TJ PCM to run the cluster if there are other easier/cheaper way to do so, I wanted to keep it just because I though it would be easier, and cheaper to run the TJ PCM/cluster.
ok.
yeah, definitely cheaper to run the TJ cluster if you have all the parts.
The whole "extra PCM just to run a cluster" feels kinda janky to me so I think I'd get an aftermarket cluster and roll with that. But to each his own.